G'day all,
A little background first.  My quad has been flying very well and quite responsive.  Yesterday I hit some scraggle while flying under a Palo Verde tree and messed up one prop quite badly.  It was quite a walk away and, because it landed right side up, I rearmed and flew it back to me.  I replaced all the props and took off for another flight only to find that when I blip the throttle I get some high frequency vibrations through the video feed that I did not notice before.
I have check everything I can think of.  Camera is tight.  Motor shaft play seems to be okay.
I took it for a flight this morning.  Did some flips and loops and split-s maneuvers and brought her back in for a landing.  The motors and ESC's were cool to the touch and the battery was slightly warm.

I cleaned out the flash memory last night so this was the only log on the board.  It looks to me (a beginner at tuning) that my YAW is out of tune.  Please correct me if I am way off base here.

If so, could this be the cause of my vibes?  If so, what should I adjust?
There don't seem to be any visible vibes through my goggles when flying gently, only when giving it a bit on the throttle.

I have attached a screen shot of my PID and here is a link to the Black Box log file https://drive.google.com/file/d/0BznaYe2...sp=sharing (I could not upload it to this post)

Cheers
Aussie

Your black box log looks fine to me. There's very little noise on the gyro traces and nothing seems to be overreacting. Maybe you could reduce your yaw P a little, but if it was flying fine before your little mishap, then any vibration you see in your video feed is going to be something mechanical.

Maybe the camera housing is good, but have you checked that the board inside the housing is still secure?

You don't say what quad or what camera, so I can't really say much more.

(07-May-2017, 06:55 PM)unseen Wrote: Your black box log looks fine to me. There's very little noise on the gyro traces and nothing seems to be overreacting. Maybe you could reduce your yaw P a little, but if it was flying fine before your little mishap, then any vibration you see in your video feed is going to be something mechanical.

Maybe the camera housing is good, but have you checked that the board inside the housing is still secure?

You don't say what quad or what camera, so I can't really say much more.

Thanks mate.  I will check the inside of the camera.  I was hoping the log would show that one of the motors was vibrating too much to give me a direction to head in.
Out of curiosity, why do you think the P gain on YAW is a little high?  (for future reference)

Cheers

I have experienced loose camera PCB in the case causing vibrations. I fixed it with a piece of foam between the back plate and PCB

(07-May-2017, 08:14 PM)Aussie In AZ Wrote: Thanks mate.  I will check the inside of the camera.  I was hoping the log would show that one of the motors was vibrating too much to give me a direction to head in.
Out of curiosity, why do you think the P gain on YAW is a little high?  (for future reference)

Cheers

Primarily because the PID controller seems to be having quite a strong reaction to a relatively minor mid throttle yaw twitch that you have. This example looks a little more extreme than it really is because I forgot to turn off expo on the explorer display before I took the screen shot.



Every time your throttle is between 1395 and 1440, there's this little twitch on the yaw gyro and quite a strong reaction to it. I can't really say much about real vibration as you would need to 'set debug=notch' or 'set debug=gyro' in the CLI and take a new log to show what the gyro is actually seeing. Without setting one of those debug options, the gyro values in the log are what's left after all the filters have worked on the raw data.

There's a long, involved and ultimately inconclusive discussion about mid throttle yaw twitches on the Betaflight Wiki: https://github.com/betaflight/betaflight...cillations-

Unless you actually feel that there's something wrong with how the quad flies (apart from possibly a loose circuit board in your camera), then just ignore what's in the log and don't worry about it. The same can be said for upgrading from the version 3.1.5 that you're currently running to the latest 3.1.7 version.

As the old saying goes, if it ain't broke, don't fix it!

(07-May-2017, 09:05 PM)oyvinla Wrote: I have experienced loose camera PCB in the case causing vibrations. I fixed it with a piece of foam between the back plate and PCB

Thanks for the tip.  I might do that anyway even if it's not lose when I take it apart

(07-May-2017, 09:33 PM)unseen Wrote: Primarily because the PID controller seems to be having quite a strong reaction to a relatively minor mid throttle yaw twitch that you have. This example looks a little more extreme than it really is because I forgot to turn off expo on the explorer display before I took the screen shot.



Every time your throttle is between 1395 and 1440, there's this little twitch on the yaw gyro and quite a strong reaction to it. I can't really say much about real vibration as you would need to 'set debug=notch' or 'set debug=gyro' in the CLI and take a new log to show what the gyro is actually seeing. Without setting one of those debug options, the gyro values in the log are what's left after all the filters have worked on the raw data.

There's a long, involved and ultimately inconclusive discussion about mid throttle yaw twitches on the Betaflight Wiki: https://github.com/betaflight/betaflight...cillations-

Unless you actually feel that there's something wrong with how the quad flies (apart from possibly a loose circuit board in your camera), then just ignore what's in the log and don't worry about it. The same can be said for upgrading from the version 3.1.5 that you're currently running to the latest 3.1.7 version.

As the old saying goes, if it ain't broke, don't fix it!

Thanks for the info mate.  I appreciate it.  I have dropped the P gain on YAW from 80 to 75 and will see what happens tomorrow.  I am not running a Gopro or he like on this rig at the moment.  I'm waiting for a mount to arrive in the post.  It will be interesting to see how bad the vibes are on an HD camera.

It's funny you mention "if it ain't broke, don't fix it".  I posed a question here http://intofpv.com/t-to-update-or-not-to...e-question about just that.  I won't be upgrading my FC until I think it's broke.

Cheers

I too had a problem with a loose pcb inside the case of my Swift 2. 
Even showed signs of shorting on the metal used in the case to hold  the screws.

    I just wanted to say thanks to you guys for your input.  I ended up dropping the YAW P gain down to 70 and the logs have smoothed out.  That was a happy bi-product of my original problem which I found the solution for thanks to you guys.  It turned out to be not the camera circuit board but the lens.  It had come lose and although it wasn't twisting and going out of focus, it was vibrating in the threads.  I put a rubber o-ring on the lens and all is right with the world of KWAD again.

Cheers guys